TWI730505B - Light conversion ink composition, light conversion pixel, color filter and display device - Google Patents

Abstract

Provided are a light conversion ink composition comprising a quantum dot and a curable monomer, wherein the quantum dot has a ligand layer comprising a specific polyethylene glycol-based ligand on the surface, and the curable monomer comprises a specific bifunctional (meth)acrylate, a color filter formed using the same, and an image display device having the color filter. The light conversion ink composition according to the present invention exhibits excellent optical properties and dispersibility of quantum dots without any solvent, and can implement low viscosity. Accordingly, the light conversion ink composition according to the present invention can be effectively used for preparing a color filter by an inkjet printing method.

Description

Light conversion ink composition, light conversion pixel, color filter and display Display device

The invention relates to a light conversion ink composition, a color filter and an image display device. More specifically, the present invention relates to a light conversion ink composition that exhibits excellent optical properties and dispersibility of quantum dots without any solvent, and can achieve low viscosity, and is formed by using the light conversion ink composition. The color filter and the image display device with the color filter.

A color filter is a thin-film optical component that can extract three colors of red, green, and blue from white light, and can be used as a pure unit pixel, and the size of the pixel ranges from about tens of microns to hundreds of microns. The color filter has the following structure: a black matrix layer is formed in a predetermined pattern on a transparent substrate to shield the boundary between each pixel; and it has a pixel portion in which multiple colors (usually red (R), green (G)) The three colors of blue (B) and blue (B)) are arranged in a predetermined order to form each pixel that is sequentially stacked.

Recently, as one of the methods for realizing color filters, a pigment dispersion method using a pigment dispersion type photosensitive resin has been applied. However, the following problems occur during the transmission of light emitted from the light source through the color filter. Part of the light is absorbed by the color filter, resulting in deterioration of light efficiency, and due to the nature of the pigment in the color filter. Decrease in color reproducibility.

In particular, since color filters are used in various fields including various image display devices, not only excellent pattern characteristics, but also performance such as high color reproducibility, high brightness, and high contrast are required. In order to solve these problems, a method of manufacturing a color filter using a self-luminous photosensitive resin composition containing quantum dots has been proposed. For example, Korean Patent Publication No. 10-2009-0036373 discloses that the luminous efficiency of the display device can be improved by using a light-emitting layer composed of quantum dot phosphors to replace traditional color filters.

The photoetching method using the photosensitive resin composition is a method of forming a color filter through coating, exposure, development, and curing. The photolithography method is excellent in the refinement and reproducibility of color filters. However, in order to form pixels, each color requires processes of coating, exposure, development, and curing, which increases manufacturing steps, time, and costs, and increases control factors between processes, resulting in difficulties in yield management.

In order to solve these problems, an inkjet method has been proposed. The inkjet method is a technology in which each type of ink realizes a color image by ejecting liquid ink with an inkjet head to separate predetermined positions. This allows multiple colors including red, green, and blue to be colored at the same time, thereby greatly reducing Manufacturing steps, time and cost.

Recently, a high degree of color reproducibility (compared to the color density of the American Television System Committee) is required in screens, televisions, etc., and therefore, there is a need to improve the luminous brightness of quantum dots. In order to improve the luminous brightness, the method of thickening the film layer can be used, but there are limitations to thickening the film layer in an ink composition containing quantum dots and a solvent. Therefore, there is a need for a solvent-free ink composition containing sub-dots.

However, in the case of preparing quantum dots in the form of a solvent-free composition, it is difficult to uniformly disperse and cause aggregation of the quantum dots. As a result, the optical properties of the quantum dots decrease or the viscosity increases, which may deteriorate the ejection properties.

Therefore, there is a need to develop an ink composition that exhibits excellent quantum dot optical properties and dispersibility without any solvent, and can achieve low viscosity.

An object of the present invention is to provide a light conversion ink composition that exhibits excellent quantum dot optical properties and dispersibility without any solvent, and can achieve low viscosity.

Another object of the present invention is to provide a light conversion pixel including a cured product of the light conversion ink composition.

Another object of the present invention is to provide a color filter including light conversion pixels.

A further object of the present invention is to provide an image display device with color filters.

〔Technical solutions〕

According to one aspect of the present invention, there is provided a light conversion ink composition comprising quantum dots and curable monomers, wherein the quantum dots have a coordination base layer, and the coordination base layer includes on the surface at least one of the following chemical formula 1a To 1e, and the curable monomer includes a compound represented by the following chemical formula 2:

〔Chemical formula 2〕

Wherein, R'and R" are each independently a hydrogen atom; a carboxyl group; a phenyl group; or an unsubstituted or substituted C ₁ -C ₂₀ alkyl group with a thiol group, and R'and R" are not hydrogen atoms at the same time; a phenyl group; Or an unsubstituted C ₁ -C ₂₀ alkyl group, R ^a , R ^b and R ^c are each independently a C ₁ -C ₂₂ alkyl group or a C ₄ -C ₂₂ alkenyl group, and R ^d is a C ₁ -C ₂₂ alkylene group , C ₃ -C ₈ cycloalkylene or C ₆ -C ₁₄ arylene, A and B each independently does not exist, or C ₁ -C ₂₂ alkylene, O, NR or S, R is hydrogen or C ₁ -C ₂₂ alkyl, X is carboxyl, phosphoric, thiol, amino, tetrazolyl, imidazolyl, pyridyl or lipoamido group, n is an integer from 1 to 20, p , Q, t and u are each independently an integer from 1 to 100, r is an integer from 1 to 10, R ¹ is C ₁ -C ₂₀ alkylene, phenylene or C ₃ -C ₁₀ cycloalkylene , R ² is hydrogen or methyl, and m is an integer from 1 to 15.

In an embodiment of the present invention, the quantum dots may be non-cadmium type quantum dots.

In an embodiment of the present invention, the quantum dot has a core-shell structure, and the core-shell structure has a core and a shell covering the core. The core may include selected from GaN, GaP, GaAs, GaSb, AlN, AlP, AlAs, AlSb, InN, InP, InAs, InSb, GaNP, GaNAS, GaNSb, GaPAs, GaPSb, AlNP, AlNAs, AlNSb, AlPAs, AlPSb, InNP At least one of the group consisting of, InNAs, InNSb, InPAs, InPSb, GaAlNP, GaAlNAs, GaAlNSb, GaAlPAs, GaAlPSb, GaInNP, GaInNAs, GaInNSb, GaInPAs, GaInPSb, InAlNP, InAlNAs, InAlNSb, InAlPAs, and InAlPSb, and The shell may include at least one selected from the group consisting of ZnSe, ZnS, and ZnTe.

The light conversion ink composition according to an embodiment of the present invention may further include scattering particles.

In an embodiment of the present invention, the scattering particles include selected from Al ₂ O ₃ , SiO ₂ , ZnO, ZrO ₂ , BaTiO ₃ , TiO ₂ , Ta ₂ O ₅ , Ti ₃ O ₅ , ITO, IZO, ATO, ZnO -At least one of the group consisting of Al, Nb ₂ O _{3, SnO and MgO.}

In an embodiment of the present invention, the scattering particles may be TiO ₂ .

The light conversion ink composition according to an embodiment of the present invention may further include a photopolymerization initiator.

The light conversion ink composition according to an embodiment of the present invention may include solventless.

According to another aspect of the present invention, there is provided a light conversion pixel including a cured product of a light conversion ink composition.

According to yet another aspect of the present invention, there is provided a color filter including light conversion pixels.

According to a further aspect of the present invention, there is provided an image display device, which is characterized by having a color filter.

〔Beneficial effect〕

The light conversion ink composition according to the present invention contains no solvent, and contains quantum dots having specific polyethylene glycol-based ligands on the surface as a colorant, and contains excellent compatibility with polyethylene glycol-based ligands. Specific bifunctional (meth)acrylates are used as curable monomers to exhibit excellent quantum dot optical properties and dispersibility, and achieve low viscosity. Therefore, the light conversion ink composition according to the present invention can be effectively used to prepare a color filter through an inkjet printing method.

[Best mode]

Hereinafter, the present invention will be described in more detail.

In the present invention, the description of one member being "on" another member includes the case where one member is adjacent to another member and the case where other members exist between two members.

In the present invention, unless otherwise disclosed, the description of a part of "comprising" elements does not exclude other elements, and means that other elements may be further included.

One embodiment of the present invention relates to a light conversion ink composition comprising quantum dots (A) and curable monomers (B), wherein the quantum dots (A) have a specific polyethylene glycol-based composition on the surface. The ligand layer of the ligand, and the curable monomer (B) includes a specific bifunctional (meth)acrylate.

〔Quantum dots (A)〕

In one embodiment of the present invention, the quantum dot has a coordination base layer on the surface, and includes at least one of the compounds represented by the following chemical formulas 1a to 1e.

Wherein, R'and R" are each independently a hydrogen atom; a carboxyl group; a phenyl group; or an unsubstituted or substituted C ₁ -C ₂₀ alkyl group with a thiol group, and R'and R" are not hydrogen atoms at the same time; a phenyl group; Or an unsubstituted C ₁ -C ₂₀ alkyl group, R ^a , R ^b and R ^c are each independently a C ₁ -C ₂₂ alkyl group or a C ₄ -C ₂₂ alkenyl group, and R ^d is a C ₁ -C ₂₂ alkylene group , C ₃ -C ₈ cycloalkylene or C ₆ -C ₁₄ arylene, A and B each independently does not exist, or C ₁ -C ₂₂ alkylene, O, NR or S, R is hydrogen or C ₁ -C ₂₂ alkyl group, X is carboxyl group, phosphoric acid group, thiol group, amino group, tetrazolyl, imidazolyl, pyridyl or lipoic amide group, n is an integer from 1 to 20, p, q, t And u are each independently an integer from 1 to 100, and r is an integer from 1 to 10.

As used herein, C ₁ -C ₂₀ alkyl refers to a linear or branched monovalent hydrocarbon composed of 1 to 20 carbon atoms, examples of which may include methyl, ethyl, n-propyl, isopropyl, n-propyl Butyl, isobutyl, tert-butyl, sec-butyl, 1-methylbutyl, 1-ethylbutyl, n-pentyl, isopentyl, neopentyl, tert-pentyl, n-hexyl, 1- Methylpentyl, 2-methylpentyl, 4-methyl-2-pentyl, 3,3-dimethylbutyl, 2-ethylbutyl, n-heptyl, 1-methylhexyl, n- Octyl, tert-octyl, 1-methylheptyl, 2-ethylhexyl, 2-propylpentyl, n-nonyl, 2,2-dimethylheptyl, n-decyl, n-undecyl Wait, but not limited to this.

As used herein, C ₁ -C ₂₂ alkyl refers to a linear or branched monovalent hydrocarbon composed of 1 to 22 carbon atoms, examples of which may include methyl, ethyl, n-propyl, isopropyl, n-propyl Butyl, isobutyl, tert-butyl, sec-butyl, 1-methylbutyl, 1-ethylbutyl, n-pentyl, isopentyl, neopentyl, tert-pentyl, n-hexyl, 1- Methylpentyl, 2-methylpentyl, 4-methyl-2-pentyl, 3,3-dimethylbutyl, 2-ethylbutyl, n-heptyl, 1-methylhexyl, n- Octyl, tert-octyl, 1-methylheptyl, 2-ethylhexyl, 2-propylpentyl, n-nonyl, 2,2-dimethylheptyl, n-decyl, n-undecyl , N-docosyl and so on, but not limited to this.

As used herein, C ₄ -C ₂₂ alkenyl refers to a linear or branched monovalent unsaturated hydrocarbon composed of 4 to 22 carbon atoms having at least one carbon-carbon double bond, and examples thereof may include butenyl , Pentenyl, hexenyl, heptenyl, octenyl, nonenyl, decenyl, undecenyl, dodecenyl, tridecenyl, tetradecenyl, ten Pentadecenyl, hexadecenyl, heptadecenyl, octadecenyl, etc., but not limited thereto.

In the C ₁ -C ₂₀ alkyl group, the C ₁ -C ₂₂ alkyl group and the C ₄ -C ₂₂ alkenyl group, one or more of the hydrogen atoms may be replaced by a C ₁ -C ₆ alkyl group or a C ₂ -C ₆ alkenyl group. , C ₂ -C ₆ alkynyl, C ₃ -C ₁₀ cycloalkyl, C ₃ -C ₁₀ heterocycloalkyl, C ₃ -C ₁₀ heterocycloalkyloxy, C ₁ -C ₆ haloalkyl, C _1- C ₆ alkoxy, C ₁ -C ₆ thioalkoxy, aryl, acyl, hydroxyl, thio, halogen, amino, alkoxycarbonyl, carboxy, carbamoyl, cyano, nitro, etc. And so on.

In the compound represented by the chemical formula 1a of the present invention, in consideration of the optical properties and dispersibility of quantum dots, and the realization of low viscosity, R′ may be a C ₁ -C ₂₀ alkyl group that is unsubstituted or substituted with a thiol group, and R" may be a carboxyl group.

In one embodiment of the present invention, specific examples of the compound represented by Chemical Formula 1a may include 2-(2-methoxyethoxy)acetic acid (2-(2-methox yethoxy)acetic acid) (WAKO Corporation), 2-[2-(2-methoxyethoxy)ethoxy]acetic acid (2-[2-(2-methoxyethoxy)ethoxy]acetic acid) (WAKO), {2-〔2-(carboxymethyl Oxy)ethoxy]ethoxy)acetic acid ({2-[2-(carboxymethoxy)ethoxy]ethoxy}acetic acid (WAKO), 2-[2-(benzyloxy)ethoxy]acetic acid ( 2-[2-(benzyloxy)ethoxy]acetic acid), (2-(carboxymethoxy)ethoxy)acetic acid ((2-(carboxymethoxy)ethoxy)acetic acid) (WAKO company), (2-butoxy (2-butoxyethoxy)acetic acid (WAKO company), carboxy-EG6-undec anethiol, etc., but not limited thereto.

In the present invention, compounds of Formula 1b represents, in consideration of the dispersibility and optical properties of quantum dots, and achieve low viscosity, R ^a may be C ₁ -C ₂₂ alkyl or C ₄ -C ₂₀ alkenyl group, and p It can be an integer from 1 to 50. In particular, when p exceeds the above range in Chemical Formula 1b, the viscosity of the light conversion ink composition may be affected.

The compound represented by the chemical formula 1b has a thiol group, and the thiol group may be bonded to the surface of the quantum dot. Compared with the ligand layer compound (for example, carboxylic acid) possessed by traditional quantum dots, the thiol group has a superior binding affinity to the surface of the quantum dot. Therefore, it has the following advantages, suppressing the dangling bond (dangling Quenching caused by surface defects of the bond and quenching caused by surface oxidation, thereby improving optical properties (luminous properties) and reliability.

In an embodiment of the present invention, in consideration of the optical properties and dispersibility of quantum dots, and the realization of low viscosity, the compound represented by Chemical Formula 1b may be at least one selected from the compounds represented by the following Chemical Formulas 1-1 to 1-6 A compound.

In the compound represented by the chemical formula 1c of the present invention, considering the optical properties and dispersibility of quantum dots, and the realization of low viscosity, q may be an integer from 1 to 50, and r may be an integer from 1 to 8. In particular, when q and r exceed the above ranges in Chemical Formula 1c, the viscosity of the light conversion ink composition may be affected.

The compound represented by the chemical formula 1c has a thiol group, and the thiol group may be bonded to the surface of the quantum dot. Compared with the ligand layer compound (for example, carboxylic acid) possessed by traditional quantum dots, the thiol group has a superior binding affinity to the surface of the quantum dot. Therefore, it has the advantage of suppressing quenching caused by surface defects such as dangling bonds, and quenching due to surface oxidation, thereby improving optical properties (luminescence properties) and reliability.

In one embodiment of the present invention, in consideration of the optical properties and dispersibility of quantum dots, and the realization of low viscosity, the compound represented by Chemical Formula 1c may be at least selected from the compounds represented by the following Chemical Formulas 1-7 to 1-12 A compound.

〔Chemical formula 1-9〕

In the compound represented by the chemical formula 1d of the present invention, considering the optical properties and dispersibility of quantum dots, and the realization of low viscosity, R ^b may be a C ₁ -C ₂₂ alkyl group or a C ₄ -C ₂₀ alkenyl group, and t It can be an integer from 1 to 50. In particular, when t exceeds the above range in the chemical formula 1d, the viscosity of the light conversion ink composition may be affected.

The compound represented by the chemical formula 1d has an amine group, and the amine group may be bonded to the surface of the quantum dot. Compared with the ligand layer compound (for example, carboxylic acid) possessed by traditional quantum dots, the amine group has a superior binding affinity to the surface of the quantum dot. Therefore, it has the advantage of suppressing quenching caused by surface defects such as dangling bonds, and quenching due to surface oxidation, thereby improving optical properties (luminescence properties) and reliability.

In an embodiment of the present invention, considering the optical properties and dispersibility of quantum dots, and the realization of low viscosity, the compound represented by Chemical Formula 1d may be at least selected from the compounds represented by the following Chemical Formulas 1-13 to 1-18 A compound.

In the compound represented by the chemical formula 1e of the present invention, considering the optical properties and dispersibility of quantum dots, and the realization of low viscosity, R ^c may be C ₁ -C ₂₂ alkyl or C ₄ -C ₂₂ alkenyl, R ^d It can be a C ₁ -C ₂₂ alkylene group, a C ₃ -C ₈ cycloalkylene group or a C ₆ -C ₁₄ arylene group, and A and B can be independently absent, or a C ₁ -C ₂₂ alkylene group, O, NR or S, R can be hydrogen or C ₁ -C ₂₂ alkyl, X can be carboxyl, phosphoric acid, thiol, amino, tetrazolyl, imidazolyl, pyridyl or lipoic amide, And u can be an integer from 1 to 50. In particular, when u exceeds the above range in the chemical formula 1e, the viscosity of the light conversion ink composition may be affected.

In one embodiment of the present invention, in consideration of the optical properties and dispersibility of quantum dots, and the realization of low viscosity, the compound represented by Chemical Formula 1e may be at least selected from the compounds represented by the following Chemical Formulas 1-19 to 1-25 A compound.

〔Chemical formula 1-23〕

The compounds represented by the chemical formulae 1a to 1e in the present invention are organic ligands that are coordinately bonded to the surface of the quantum dot. Therefore, they can act as stabilizing quantum dots.

The quantum dot prepared by the traditional method has a coordination base layer on the surface immediately after preparation, and the coordination base layer can be composed of oleic acid, lauric acid, and the like. Compared with quantum dots including the compounds represented by the chemical formulas 1a to 1e of the present invention as the coordination base layer, the binding affinity to the quantum dots in this case is weaker. Therefore, the effect of surface protection may be deteriorated due to non-bonding defects on the surface of the quantum dots. In addition, oleic acid can be well dispersed in volatile organic compound (VOC) aliphatic hydrocarbon solvents (for example, n-hexane) and aromatic hydrocarbon solvents (for example, benzene), but in, for example, propylene glycol methyl ether acetate ( PGMEA) has poor dispersibility in solvents. The quantum dot of the present invention contains the compounds represented by the chemical formulas 1a to 1e as a coordination base layer, and therefore has very excellent dispersibility in a solvent such as propylene glycol methyl ether acetate, thereby giving it an effect of improving optical properties.

And, the quantum dot includes at least one polyethylene glycol-based ligand of the compound represented by the chemical formulas 1a to 1e, thereby being able to exhibit good dispersibility in the curable monomer described below without any solvent.

The compounds represented by the chemical formulas 1a to 1e can cover more than 5% of the total surface area of the quantum dots.

Here, the content of the compound represented by the chemical formulas 1a to 1e may be 0.1-10 mol relative to 1 mol of quantum dots.

The coordination base layer including the compounds represented by the chemical formulas 1a to 1e may have a thickness of 0.1 nanometer to 2 nanometers, for example, 0.5 nanometer to 1.5 nanometers.

In an embodiment of the present invention, quantum dots may refer to nano-sized semiconductor materials. Atoms form molecules, and molecules form aggregates of small molecules called clusters, which in turn form nanoparticles. When these nanoparticles have semiconductor properties, they are called quantum dots. When quantum dots receive energy from the outside and reach an excited state, they emit energy corresponding to the quantum dot's unique band gap. For example, the light conversion ink composition of the present invention includes the quantum dots, so that incident blue light can be converted into green light or red light.

In an embodiment of the present invention, the quantum dots may be non-cadmium type quantum dots.

The non-cadmium type quantum dots are not particularly limited, as long as they are quantum dot particles that can emit light when excited by light. For example, they can be selected from group II-VI semiconductor compounds; group III-V semiconductor compounds; group IV-VI semiconductors Compounds; Group IV elements or compounds containing said elements; and combinations of the above. They can be used alone or in combination of two or more kinds thereof.

Specifically, the group II-VI semiconductor compound can be selected from the group consisting of binary compounds, which are composed of ZnS, ZnSe, ZnTe, ZnO, HgS, HgSe, HgTe, and mixtures of the foregoing; composed of ternary compounds A group consisting of ZnSeS, ZnSeTe, ZnSTe, HgSeS, HgSeTe, HgSTe, HgZnS, HgZnSe, HgZnTe, and mixtures of the above; a group consisting of quaternary compounds consisting of HgZnSeS, HgZnSeTe, HgZnSTe, and mixtures of the above Composition, but not limited to this.

Group III-V semiconductor compounds can be selected from the group consisting of binary compounds, which are composed of GaN, GaP, GaAs, GaSb, AlN, AlP, AlAs, AlSb, InN, InP, InAs, InSb, and mixtures of the foregoing; A group consisting of ternary compounds consisting of GaNP, GaNAS, GaNSb, GaPAs, GaPSb, AlNP, AlNAs, AlNSb, AlPAs, AlPSb, InNP, InNAs, InNSb, InPAs, InPSb, GaAlNP and mixtures of the foregoing; and A group consisting of quaternary compounds, which is composed of GaAlNAs, GaAlNSb, GaAlPAs, GaAlPSb, GaInNP, GaInNAs, GaInNSb, GaInPAs, GaInPSb, InAlNP, InAlNAs, InAlNSb, InAlPAs, InAlPSb, and mixtures of the foregoing, but not limited thereto.

The group IV-VI semiconductor compound may be at least one selected from the group consisting of binary compounds, which is composed of SnS, SnSe, SnTe, SnTe, PbS, PbSe, PbTe, and mixtures of the foregoing; it is composed of a ternary compound Group At least one of SnSeS, SnSeTe, SnSTe, PbSeS, PbSeTe, PbSTe, SnPbS, SnPbSe, SnPbTe, and mixtures thereof; and at least one of the group consisting of quaternary compounds, which is composed of SnPbSSe , SnPbSeTe, SnPbSTe and the above mixture, but not limited to this.

The group IV element or the compound containing the group IV element may be an element selected from the group consisting of Si, Ge and a mixture thereof; a binary compound selected from the group consisting of SiC, SiGe and The above mixture is composed, but not limited to this.

The quantum dot may have a homogeneous single structure; for example, a dual structure of core-shell and gradient structure; or a mixed structure thereof. Preferably, the quantum dot may have a core-shell structure with a core and a shell covering the core.

Specifically, in the core-shell dual structure, the material forming each of the core and the shell may be composed of the above-mentioned different semiconductor compounds. For example, the core may include at least one selected from the group consisting of: GaN, GaP, GaAs, GaSb, AlN, AlP, AlAs, AlSb, InN, InP, InAs, InSb, GaNP, GaNAS, GaNSb, GaPAs , GaPSb, AlNP, AlNAs, AlNSb, AlPAs, AlPSb, InNP, InNAs, InNSb, InPAs, InPSb, GaAlNP, GaAlNAs, GaAlNSb, GaAlPAs, GaAlPSb, GaInNP, GaInNAs, GaInNSb, GaInPAs, GaInPSAl, InAlNPs, And InAlPSb, and the shell may include at least one selected from the group consisting of ZnSe, ZnS, and ZnTe, but they are not limited thereto.

For example, as quantum dots having a core-shell structure, InP/ZnS, InP/ZnSe, InP/GaP/ZnS, InP/ZnSe/ZnS, InP/ZnSeTe/ZnS, and InP/MnSe/ZnS can be exemplified.

The quantum dots can be synthesized by wet chemical process, metal organic chemical vapor deposition (MOCVD) or molecular beam epitaxy (MBE), but it is not limited thereto. Since quantum dots with excellent optical properties can be obtained, it is preferable to synthesize the quantum dots by a wet chemical method.

The wet chemical process is a method of growing particles by adding precursor materials to an organic solvent. When the crystal grows, the organic solvent naturally coordinates with the surface of the quantum dot crystal to act as a dispersant, thereby controlling the growth of the crystal. Therefore, compared with vapor deposition methods such as metal organic chemical vapor deposition or molecular beam epitaxy, the growth of nanoparticles can be controlled by an easier and cheaper method. Therefore, it is preferable to manufacture the quantum dots by a wet chemical process.

When preparing quantum dots by a wet chemical process, organic ligands are used to prevent aggregation of the quantum dots and control the particle size of the quantum dots to the nanometer level. Generally, oleic acid can be used as an organic ligand.

In an embodiment of the present invention, through a ligand exchange reaction, the oleic acid used in the preparation of quantum dots can be replaced with at least one polyethylene glycol-based compound among the compounds represented by the chemical formulas 1a to 1e.

It is possible to add a desired organic ligand (ie, at least one polyethylene glycol-based compound among the compounds represented by Chemical Formulas 1a to 1e) to a quantum dot containing an existing organic ligand (ie, oleic acid) Ligand Crossing In other words, it is followed by stirring at room temperature to 200° C. for 30 minutes to 3 hours to obtain quantum dots bonded to at least one polyethylene glycol-based compound among the compounds represented by chemical formulas 1a to 1e. According to requirements, the following steps can be further performed to separate and purify quantum dots bonded to at least one polyethylene glycol-based compound among the compounds represented by the chemical formulas 1a to 1e.

Based on 100% by weight of the total light conversion ink composition, the content of quantum dots may be 1 to 60% by weight, preferably 5 to 50% by weight. If the quantum dot is within the above range, it has the advantages of excellent luminous efficiency and excellent reliability of the coating layer. If the content of quantum dots is less than the above range, the light conversion efficiency of green light and red light may be insufficient. If the content of quantum dots exceeds the above range, the emission of blue light may be relatively reduced, thereby causing a problem of deterioration of color reproducibility.

〔Curable Monomer (B)〕

In one embodiment of the present invention, the curable monomer (B) includes a compound represented by the following Chemical Formula 2.

Wherein, R ¹ is a C ₁ -C ₂₀ alkylene group, a phenylene group or a C ₃ -C ₁₀ cycloalkylene group, R ² is hydrogen or a methyl group, and m is an integer from 1 to 15.

As used herein, C ₁ -C ₂₀ alkylene refers to a straight or branched divalent hydrocarbon composed of 1 to 20 carbon atoms, and examples thereof may include methylene, ethylene, n-propylene, isopropyl Propylene, n-butylene, isobutylene, n-pentene, n-hexene, n-heptene, n-octene, n-nonene, etc., but not limited thereto.

As used herein, a C ₃ -C ₁₀ cycloalkylene group refers to a simple or fused cyclic divalent hydrocarbon composed of 3 to 10 carbon atoms, and examples thereof may include cyclopropene, cyclobutene Ene, cyclopentene, cyclohexene, etc., but not limited thereto.

At least one hydrogen atom in the C ₁ -C ₂₀ alkylene group, phenylene group or C ₃ -C _{10 cycloalkylene group may be C 1} -C ₆ alkyl group, C ₂ -C ₆ alkenyl group, C ₂ -C ₆ alkynyl, C ₃ -C ₁₀ cycloalkyl, C ₃ -C ₁₀ heterocycloalkyl, C ₃ -C ₁₀ heterocycloalkoxy, C ₁ -C ₆ haloalkyl, C ₁ -C ₆ alkoxy , C ₁ -C ₆ thioalkoxy, aryl, acyl, hydroxy, thio, halogen, amino, alkoxycarbonyl, carboxy, aminomethanyl, cyano, nitro and the like.

In an embodiment of the present invention, R ¹ may be a C ₁ -C ₂₀ alkylene group, preferably a C ₁ -C ₁₂ alkylene group. When R ¹ is a C ₁ -C ₂₀ alkylene group, the scattering particles have excellent dispersibility without any solvent, thereby improving jetting performance and enhancing the hardness and surface properties of the coating film.

In an embodiment of the present invention, m is an integer from 1 to 15, preferably 1 to 5. If m exceeds the above range, the dispersibility may decrease due to high viscosity.

Specific examples of the compound represented by Chemical Formula 2 may include 1,6-hexanediol diacrylate (1,6-hexanediol diacrylate), 1,9-bisacrylic acid 1,9-bisacryloyloxynonane, tripropylene glycol diacrylate, etc.

The compound represented by Chemical Formula 2 has excellent compatibility with the polyethylene glycol-based ligands represented by Chemical Formulas 1a to 1e, thereby improving the dispersibility of quantum dots. Therefore, a low-viscosity light conversion ink composition with excellent optical performance can be realized without any solvent. Therefore, the light conversion ink composition according to the present invention can be effectively applied to the preparation of color filters through the inkjet printing method.

In addition to the polymerizable compound represented by Chemical Formula 2, the light conversion ink composition of the present invention may also include polymerizable compounds commonly used in the technical field within a range that does not impair the purpose of the present invention. For example, monofunctional monomers, bifunctional monomers, other polyfunctional monomers, etc. can be used. Among them, bifunctional monomers are preferred.

The monofunctional monomer is not particularly limited, and may include, for example, nonylphenylcarbitol acrylate, 2-hydroxy-3-phenoxypropyl acrylate, 2-ethylhexylcarbitol acrylate, 2-hydroxyethyl acrylate, N-vinylpyrrolidone, etc.

The bifunctional monomer is not particularly limited, and may include, for example, bis(acryloyloxyethyl)ether of bisphenol A and the like.

The multifunctional monomer is not particularly limited and may include, for example, trimethylolpropane tri(meth)acrylate (trimethylolpropane tri(meth)acrylate), ethoxylated trimethylolpropane tri(meth)acrylate (ethoxylated trimethylolpropane tri(meth)acrylate), propoxylated trimethylolpropane tri(meth)acrylate, pentaerythritol tri(meth)acrylate acrylate), pentaerythritol tetra(meth)acrylate, dipentaerythriol tri(meth)acrylate (dipentaerythriol tri(meth)acrylate), dipentaerythriol penta(meth)acrylate (dipentaerythriol penta (meth)acrylate), ethoxylated dipentaerythritol hexa(meth)acrylate, propoxylated dipentaerythritol hexa(meth)acrylate ), dipentaerythriol hexa(meth)acrylate and so on.

Based on 100% by weight of the entire light conversion ink composition, the content of the curable monomer (B) may be 20 to 90% by weight, preferably 30 to 80% by weight. When the curable monomer is included in the above range, it has an advantage in terms of the strength or smoothness of the pixel portion. When the content of the curable monomer is less than the above range, the strength of the pixel portion may slightly decrease, and when the content of the curable monomer exceeds the above range, the smoothness may decrease. Therefore, it is preferable to include the curable monomer within the above-mentioned range.

〔Scattering particles (C)〕

The light conversion ink composition according to an embodiment of the present invention may further include scattering particles (C).

The scattering particles increase the light path emitted from the quantum dots, thereby enhancing the overall light efficiency.

As the scattering particles, conventional inorganic materials can be used. Preferably, metal oxides can be used.

The metal oxide may be an oxide containing a metal, and the metal is selected from Li, Be, B, Na, Mg, Al, Si, K, Ca, Sc, V, Cr, Mn, Fe, Ni, Cu, Zn, Ga, Ge, Rb, Sr, Y, Mo, Cs, Ba, La, Hf, W, Tl, Pb, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Ti, Sb, Sn, Zr, Nb, Ce, Ta, In, and a combination of the above, but not limited to this group.

Specifically, it can be selected from Al ₂ O ₃ , SiO ₂ , ZnO, ZrO ₂ , BaTiO ₃ , TiO ₂ , Ta ₂ O ₅ , Ti ₃ O ₅ , ITO, IZO, ATO, ZnO-Al, Nb ₂ O _3. One of the group consisting of SnO, MgO and the above combination. If necessary, a material surface-treated with a compound having an unsaturated bond (for example, acrylate) can be used.

The scattering particles may have an average particle diameter of 50 to 1,000 nanometers, preferably 100 to 500 nanometers, and more preferably 150 to 300 nanometers. If the particle size is too small, it cannot be expected to exhibit a sufficient scattering effect of the light emitted from the quantum dots. On the contrary, such as If the particle size is too large, the particles may sink into the composition, or a light conversion layer surface with uniform quality may not be obtained. Therefore, the particle size is appropriately controlled within the above range.

Here, the average particle size may be a number average particle size, and can be obtained, for example, from an image observed in a field emission scanning electron microscope (FE-SEM) or a transmission electron microscope (TEM). Specifically, the number average particle size can be obtained by taking out several samples from the images observed by the field emission scanning electron microscope or the transmission electron microscope, measuring the diameter of the samples, and calculating the arithmetic average value.

Based on 100% by weight of the total light conversion ink composition, the content of the scattering particles may be 0.5 to 20% by weight, preferably 1 to 15% by weight. When the scattering particles are included in the above range, the effect of increasing the luminous intensity can be maximized. When the content of the scattering particles is less than the above range, the desired luminous intensity may not be obtained. When the content of the scattering particles exceeds the above range, the transmittance of blue irradiated light may decrease, which may cause problems with luminous efficiency.

〔Photopolymerization initiator (D)〕

The light conversion ink composition according to an embodiment of the present invention may further include a photopolymerization initiator (D).

系化合物所組成。 In one embodiment of the present invention, the photopolymerization initiator (D) can be used without particular limitation, as long as the curable monomer can be polymerized. In particular, in consideration of polymerization performance, initial efficiency, absorption wavelength, availability, cost, etc., as the photopolymerization initiator (D), it is preferable to use at least one compound selected from the following group: The group consists of acetophenone compounds, benzophenone compounds, triazine compounds, diimidazole compounds, oxime compounds and 9-oxysulfur

Department of compounds.

Based on 100% by weight of the total light conversion ink composition, the content of the photopolymerization initiator (D) may be 0.01 to 20% by weight, preferably 0.5 to 15% by weight. When the photopolymerization initiator is contained in the above range, the light conversion ink composition is highly sensitized to shorten the exposure time, and thus the productivity can be improved. In addition, there are advantages in that the intensity of the pixel portion formed using the light conversion ink composition according to the present invention and the surface smoothness of the pixel portion become more favorable.

In order to enhance the sensitivity of the light conversion ink composition according to the present invention, the photopolymerization initiator (D) may further include a photopolymerization initiator (d1). When the photopolymerization initiation aid is included, there is an advantage of further improving sensitivity and thus productivity.

The photopolymerization initiation assistant (d1) may preferably be at least one selected from the group consisting of amine compounds, carboxylic acid compounds, and organosulfur compounds having a thiol group, but is not limited thereto.

The photopolymerization initiation aid (d1) can be appropriately added within a range that does not impair the efficacy of the present invention.

〔Additives (E)〕

In addition to the above-mentioned components, the light conversion ink composition according to an embodiment of the present invention may further include additives such as surfactants and adhesion promoters to enhance the smoothness or adhesion of the coating film.

When the light conversion ink composition according to the present invention contains a surfactant, it has the advantage that it can improve the smoothness of the coating film. The surfactant can be, for example, a fluorine-based surfactant, such as BM-1000, BM-1100 (BM Chemie), Fluorad FC-135/FC-170C/FC-430 (SUMITOMO 3M Limited), SH-28PA/-190 /-8400/SZ-6032 (Toray Silicone Co., Ltd.) etc., but not limited to this.

Adhesion promoters can be added to increase adhesion to the substrate, and can include silane coupling agents with reactive substituents selected from carboxyl groups, methacrylic groups, isocyanate groups, epoxy groups and The combination of the above, but not limited to this.

In addition, the light conversion ink composition according to the present invention may further contain additives such as antioxidants, ultraviolet absorbers, and anti-blocking agents within a range that does not impair the effects of the present invention. Those having ordinary knowledge in the technical field of the present invention can appropriately add and use additives within a range that does not impair the effects of the present invention.

Based on 100% by weight of the total light conversion ink composition, the amount of the additive may be 0.05 to 10% by weight, particularly 0.1 to 10% by weight, more particularly 0.1 to 5% by weight, but is not limited thereto.

The light conversion ink composition according to an embodiment of the present invention contains substantially no solvent. Even if the solvent is included, its content is 2% by weight or less of 100% by weight of the entire light conversion ink composition. Even if the light conversion ink composition according to an embodiment of the present invention is a solvent-free composition containing no solvent, it still has excellent quantum dot optical properties and dispersibility, and can achieve low viscosity.

In addition, the light conversion ink composition according to an embodiment of the present invention does not substantially contain a resin component. Even if the resin component is contained, its content is 0.5% by weight or less based on 100% by weight of the entire light conversion ink composition. The light conversion ink composition according to an embodiment of the present invention does not contain a resin component, and therefore can achieve low viscosity, thereby having excellent nozzle ejection performance of ink.

An embodiment of the present invention relates to a light conversion pixel, which includes a cured product of the above light conversion ink composition.

In addition, an embodiment of the present invention relates to a color filter including the above-mentioned light conversion pixel.

The method for forming a pattern of a light conversion ink composition according to the present invention includes a step of applying the above-mentioned light conversion ink composition on a predetermined area by an inkjet method, and a step of curing the applied light conversion ink composition.

First, the light conversion ink composition of the present invention is injected into an inkjet device and printed on a predetermined area of the substrate.

The substrate is not limited, and examples thereof may include substrates having flat surfaces, such as glass substrates, polysiloxy plates, polycarbonate substrates, polyester substrates, aromatic polyamide substrates, polyimide imide substrates, Polyimide substrate, aluminum substrate and gallium arsenide substrate. These substrates can be pretreated, for example, chemical treatment, plasma treatment, ion plating treatment, sputtering treatment, gas phase reaction treatment and vacuum deposition treatment through chemical substances (such as silane coupling agent). When a polysiloxy plate or the like is used as a substrate, it is possible to form electricity on the surface of the polysiloxy plate or the like. Charge coupled device (CCD), thin film transistor (TFT) and so on. In addition, a partition wall matrix can be formed thereon.

In order to be able to eject from a piezoelectric inkjet head (as an example of an inkjet device) to form an appropriate phase state on the substrate, the properties of viscosity, fluidity, quantum dot particles, etc. should be balanced with the inkjet head. The piezoelectric inkjet head used in the present invention is not limited, but the ejected ink has a droplet size of about 10 to 100 pL, preferably 20 to 40 pL.

The suitable range of the viscosity of the light conversion ink composition of the present invention is about 3 to 30 cP, and it is more preferable to control it in the range of 7 to 20 cP.

The color filter according to an embodiment of the present invention includes a color pattern layer formed by a pattern forming method. In other words, the color filter is characterized by including a color pattern layer, which is formed by coating the above-mentioned light conversion ink composition on a substrate in a predetermined pattern and then curing it. Since the components and preparation methods of the color filter are well known in the technical field of the present invention, detailed descriptions thereof are omitted.

An embodiment of the present invention relates to an image display device having the above-mentioned color filter.

The color filter of the present invention is not only suitable for traditional liquid crystal display devices (LCD), but also suitable for various image display devices, such as electroluminescence display devices (EL), plasma display devices (PDP), field emission display devices ( FED), Organic Light Emitting Diode (OLED), etc.

In addition to the above-mentioned color filter, the image display device of the present invention also has constituent elements well known in the art.

Hereinafter, the present invention will be described in more detail through examples, comparative examples, and experimental examples. However, these Examples, Comparative Examples, and Experimental Examples are presented for illustrative purposes only, and it is obvious to those having ordinary knowledge in the technical field of the present invention that the scope of the present invention is not limited thereto.

[Synthesis Example 1: Synthesis of Ligand Substituted Quantum Dots (A1)]

0.4 mmol (0.058 g) of indium acetate, 0.6 mmol (0.15 g) of palmitic acid, and 20 mL of 1-octadecene were added to the reactor and heated to 120°C in vacuum. After 1 hour, the atmosphere in the reactor was converted to nitrogen. After the mixture was heated to 280°C, a mixed solution of 0.2 mmol (58 μl ) of tris(trimethylsilyl)phosphine (TMS3P) and 1.0 mL of trioctylphosphine was quickly injected into it and reacted for 1 minute.

2.4mmol (0.448g) of zinc acetate, 4.8mmol of oleic acid and 20mL of trioctylamine were added to the reactor and heated to 120°C under vacuum. After 1 hour, the atmosphere in the reactor was converted to nitrogen, and the reactor temperature was increased to 280°C. 2ml of the previously synthesized InP core solution was added, then 4.8mmol of selenium in trioctylphosphine solution (Se/TOP) was added thereto, and the final mixture was allowed to react for 2 hours. Ethanol was added to the reaction solution that was rapidly cooled to room temperature, and centrifuged. The obtained precipitate was filtered under reduced pressure, and then dried under reduced pressure to obtain a core-shell of InP/ZnSe.

Subsequently, 2.4 mmol (0.448 g) of zinc acetate, 4.8 mmol of oleic acid and 20 mL of trioctylamine were added to the reactor and heated to 120°C under vacuum. After 1 hour, the atmosphere in the reactor was converted to nitrogen, and the reactor temperature was increased to 280°C. 2ml of the previously synthesized InP/ZnSe core-shell solution was added, then 4.8mmol of sulfur trioctylphosphine solution (S/TOP) was added thereto, and the final mixture was allowed to react for 2 hours. Ethanol was added to the reaction solution that was rapidly cooled to room temperature, and centrifuged. The obtained precipitate was filtered under reduced pressure, and then dried under reduced pressure. The obtained quantum dots with InP/ZnSe/ZnS core-shell structure are dispersed in chloroform.

The obtained nano quantum dots showed a maximum luminescence peak at 535nm in the light-excited fluorescence spectrum. 5ml of the quantum dot solution was added to the centrifuge tube, and then precipitated by adding 20mL of ethanol. The supernatant was removed by centrifugation, and 2 mL of chloroform was added to the precipitate to disperse the quantum dots. Thereafter, 0.50 g of (2-butoxyethoxy)acetic acid was added thereto, followed by reaction under a nitrogen atmosphere for 1 hour while heating to 60°C.

Subsequently, the quantum dots were precipitated by adding 25 mL of n-hexane, followed by centrifugation to obtain a precipitate.

[Synthesis Example 2: Synthesis of Ligand Substituted Quantum Dots (A2)]

0.4 mmol (0.058 g) of indium acetate, 0.6 mmol (0.15 g) of palmitic acid and 20 mL of 1-octadecene were added to the reactor and heated to 120°C under vacuum. After 1 hour, the atmosphere in the reactor was converted to nitrogen. After the mixture was heated to 280°C, a mixed solution of 0.2mmol (58 μl ) of tris(trimethylsilyl)phosphine (TMS3P) and 1.0mL of trioctylphosphine was quickly injected into it, and reacted for 5 minutes, then quickly Cool to room temperature. The maximum absorption wavelength is 560 to 590 nm.

2.4mmol (0.448g) of zinc acetate, 4.8mmol of oleic acid and 20mL of trioctylamine were added to the reactor and heated to 120°C under vacuum. After 1 hour, the atmosphere in the reactor was converted to nitrogen, and the reactor temperature was increased to 280°C. 2ml of the previously synthesized InP core solution was added, and then 4.8mmol of selenium in trioctylphosphine solution (Se/TOP) was added to it. The final mixture was allowed to react for 2 hours, and then cooled to room temperature to obtain a core-shell of InP/ZnSe.

Subsequently, 2.4 mmol (0.448 g) of zinc acetate, 4.8 mmol of oleic acid and 20 mL of trioctylamine were added to the reactor and heated to 120°C under vacuum. After 1 hour, the atmosphere in the reactor was converted to nitrogen, and the reactor temperature was increased to 280°C. 2ml of the previously synthesized InP/ZnSe core-shell solution was added, then 4.8mmol of sulfur trioctylphosphine solution (S/TOP) was added thereto, and the final mixture was allowed to react for 2 hours. Ethanol was added to the reaction solution that was rapidly cooled to room temperature, and centrifuged. The obtained precipitate was filtered under reduced pressure and then dried under reduced pressure to obtain quantum dots having an InP/ZnSe/ZnS core-shell structure, which was then dispersed in chloroform.

The obtained nano quantum dots showed a maximum luminescence peak at 635 nm in the light-excited fluorescence spectrum, and 5 ml of the synthesized quantum dot solution was added to a centrifuge tube and precipitated by adding 20 mL of ethanol. The supernatant was removed by centrifugation, and 2 mL of chloroform was added to the precipitate to disperse the quantum dots. After that, 0.65 g of carboxyl-EG6-undecanethiol was added thereto, and the mixture was heated to 60° C. under a nitrogen atmosphere while reacting for 1 hour.

Subsequently, the quantum dots were precipitated by adding 25 mL of n-hexane, followed by centrifugation to remove the supernatant to obtain a precipitate.

[Synthesis Example 3: Synthesis of Ligand Substituted Quantum Dots (A3)]

0.4 mmol (0.058 g) of indium acetate, 0.6 mmol (0.15 g) of palmitic acid, and 20 mL of 1-octadecene were added to the reactor and heated to 120°C under vacuum. After 1 hour, the atmosphere in the reactor was converted to nitrogen.

After the mixture was heated to 280°C, a mixed solution of 0.2 mmol (58 μl ) of tris(trimethylsilyl)phosphine (TMS3P) and 1.0 mL of trioctylphosphine was quickly injected into it and reacted for 0.5 minutes.

Subsequently, 2.4 mmol (0.448 g) of zinc acetate, 4.8 mmol of oleic acid, and 20 mL of trioctylamine were added to the reactor and heated to 120°C under vacuum. After 1 hour, the atmosphere in the reactor was converted to nitrogen, and the reactor temperature was increased to 280°C. 2ml of the previously synthesized InP core solution was added, then 4.8mmol of selenium in trioctylphosphine solution (Se/TOP) was added thereto, and the final mixture was allowed to react for 2 hours. Ethanol was added to the reaction solution that was rapidly cooled to room temperature, and centrifuged. The obtained precipitate was filtered under reduced pressure, and then dried under reduced pressure to obtain a core-shell of InP/ZnSe.

Subsequently, 2.4 mmol (0.448 g) of zinc acetate, 4.8 mmol of oleic acid, and 20 mL of trioctylamine were added to the reactor and heated to 120°C under vacuum. After 1 hour, the atmosphere in the reactor was converted to nitrogen, and the reactor temperature was increased to 280°C. Add 2ml of the previously synthesized InP/ZnSe core-shell solution, then add 4.8mmol of sulfur trioctylphosphine solution (S/TOP) to it, and make the final mixing The reaction was for 2 hours. Ethanol was added to the reaction solution that was rapidly cooled to room temperature, and centrifuged. The obtained precipitate was filtered under reduced pressure and then dried under reduced pressure to obtain quantum dots having an InP/ZnSe/ZnS core-shell structure, which was then dispersed in chloroform. The solid content is controlled at 10%. The maximum emission wavelength is 520nm.

Add 5ml of the synthesized quantum dot solution into a centrifuge tube, and precipitate by adding 20ml of ethanol. The supernatant was removed by centrifugation, and 3 mL of chloroform was added to the precipitate to disperse the quantum dots. After that, 1.00 g of mPEG5-SH (FutureChem Co, Ltd.) represented by the following chemical formula 1-1 was added thereto, followed by a reaction for 1 hour while heating to 60°C in a nitrogen atmosphere.

Subsequently, 25 mL of n-hexane was added to precipitate the quantum dots, and then the supernatant was removed by centrifugation to obtain a precipitate.

[Synthesis Example 4: Synthesis of Ligand Substituted Quantum Dots (A4)]

The quantum dots were synthesized in the same manner as in Synthesis Example 3 except that mPEG7-SH (FutureChem Co, Ltd.) represented by the following Chemical Formula 1-2 was used instead of the ligand used in Synthesis Example 3.

[Synthesis Example 5: Synthesis of Ligand Substituted Quantum Dots (A5)]

The quantum dots were synthesized in the same manner as in Synthesis Example 3 except that the compound represented by the following Chemical Formula 1-3 was used instead of the ligand used in Synthesis Example 3.

[Synthesis Example 6: Synthesis of Ligand Substituted Quantum Dots (A6)]

The quantum dots were synthesized in the same manner as in Synthesis Example 3 except that the compound represented by the following Chemical Formula 1-4 was used instead of the ligand used in Synthesis Example 3.

[Synthesis Example 7: Synthesis of Ligand Substituted Quantum Dots (A7)]

The quantum dots were synthesized in the same manner as in Synthesis Example 3 except that the compound represented by the following Chemical Formula 1-5 was used instead of the ligand used in Synthesis Example 3.

[Synthesis Example 8: Synthesis of Ligand Substituted Quantum Dots (A8)]

The quantum dots were synthesized in the same manner as in Synthesis Example 3 except that the compound represented by the following Chemical Formula 1-6 was used instead of the ligand used in Synthesis Example 3.

[Synthesis Example 9: Synthesis of Ligand Substituted Quantum Dots (A9)]

The quantum dots were synthesized in the same manner as in Synthesis Example 3 except that 3.00 g of the compound represented by the following Chemical Formula 1-7 was used instead of 1.00 g of the ligand used in Synthesis Example 3.

[Synthesis Example 10: Synthesis of Ligand Substituted Quantum Dots (A10)]

The quantum dots were synthesized in the same manner as in Synthesis Example 3 except that 3.00 g of the compound represented by the following Chemical Formula 1-8 was used instead of 1.00 g of the ligand used in Synthesis Example 3.

[Synthesis Example 11: Synthesis of Ligand Substituted Quantum Dots (A11)]

The quantum dots were synthesized in the same manner as in Synthesis Example 3 except that 3.00 g of the compound represented by the following Chemical Formula 1-9 was used instead of 1.00 g of the ligand used in Synthesis Example 3.

[Synthesis Example 12: Synthesis of Ligand Substituted Quantum Dots (A12)]

The quantum dots were synthesized in the same manner as in Synthesis Example 3 except that 3.00 g of the compound represented by the following Chemical Formula 1-10 was used instead of 1.00 g of the ligand used in Synthesis Example 3.

[Synthesis Example 13: Synthesis of Ligand Substituted Quantum Dots (A13)]

The quantum dots were synthesized in the same manner as in Synthesis Example 3 except that 3.00 g of the compound represented by the following Chemical Formula 1-11 was used instead of 1.00 g of the ligand used in Synthesis Example 3.

[Synthesis Example 14: Synthesis of Ligand Substituted Quantum Dots (A14)]

The quantum dots were synthesized in the same manner as in Synthesis Example 3 except that 3.00 g of the compound represented by the following Chemical Formula 1-12 was used instead of 1.00 g of the ligand used in Synthesis Example 3.

[Synthesis Example 15: Synthesis of Ligand Substituted Quantum Dots (A15)]

The quantum dots were synthesized in the same manner as in Synthesis Example 3 except that 3.00 g of the compound represented by the following Chemical Formula 1-13 was used instead of 1.00 g of the ligand used in Synthesis Example 3.

[Synthesis Example 16: Synthesis of Ligand Substituted Quantum Dots (A16)]

The quantum dots were synthesized in the same manner as in Synthesis Example 3, except that 3.00 g of the compound represented by the following Chemical Formula 1-14 was used instead of 1.00 g of the ligand used in Synthesis Example 3.

[Synthesis Example 17: Synthesis of Ligand Substituted Quantum Dots (A17)]

The quantum dots were synthesized in the same manner as in Synthesis Example 3 except that 3.00 g of the compound represented by the following Chemical Formula 1-15 was used instead of 1.00 g of the ligand used in Synthesis Example 3.

[Synthesis Example 18: Synthesis of Ligand Substituted Quantum Dots (A18)]

The quantum dots were synthesized in the same manner as in Synthesis Example 3 except that 3.00 g of the compound represented by the following Chemical Formula 1-16 was used instead of 1.00 g of the ligand used in Synthesis Example 3.

[Synthesis Example 19: Synthesis of Ligand Substituted Quantum Dots (A19)]

The quantum dots were synthesized in the same manner as in Synthesis Example 3 except that 3.00 g of the compound represented by the following Chemical Formula 1-17 was used instead of 1.00 g of the ligand used in Synthesis Example 3.

[Synthesis Example 20: Synthesis of Ligand Substituted Quantum Dots (A20)]

The quantum dots were synthesized in the same manner as in Synthesis Example 3 except that 3.00 g of the compound represented by the following Chemical Formula 1-18 was used instead of 1.00 g of the ligand used in Synthesis Example 3.

[Comparative Synthesis Example 1: Synthesis of Quantum Dots with Unsubstituted Ligands (A21)]

0.4 mmol (0.058 g) of indium acetate, 0.6 mmol (0.15 g) of palmitic acid, and 20 mL of 1-octadecene were added to the reactor and heated to 120°C under vacuum. After 1 hour, the atmosphere in the reactor was converted to nitrogen. After the mixture is heated to 280°C, a mixed solution of 0.2mmol (58 μl ) of tris(trimethylsilyl)phosphine (TMS3P) and 1.0mL of trioctylphosphine is quickly injected into it, and the mixture is rapidly cooled after 5 minutes of reaction To room temperature. The maximum absorption wavelength is 560 to 590 nm.

2.4mmol (0.448g) of zinc acetate, 4.8mmol of oleic acid and 20mL of trioctylamine were added to the reactor and heated to 120°C under vacuum. After 1 hour, the atmosphere in the reactor was converted to nitrogen, and the reactor temperature was increased to 280°C. 2ml of the previously synthesized InP core solution was added, and then 4.8mmol of selenium in trioctylphosphine solution (Se/TOP) was added to it. The final mixture was allowed to react for 2 hours, and then cooled to room temperature to obtain a core-shell of InP/ZnSe.

Subsequently, 2.4 mmol (0.448 g) of zinc acetate, 4.8 mmol of oleic acid, and 20 mL of trioctylamine were added to the reactor and heated to 120 mL under vacuum. ℃. After 1 hour, the atmosphere in the reactor was converted to nitrogen, and the reactor temperature was increased to 280°C. 2ml of the previously synthesized InP/ZnSe core-shell solution was added, then 4.8mmol of sulfur trioctylphosphine solution (S/TOP) was added thereto, and the final mixture was allowed to react for 2 hours. Ethanol was added to the reaction solution that was rapidly cooled to room temperature, and centrifuged. The obtained precipitate was filtered under reduced pressure and then dried under reduced pressure to obtain quantum dots having an InP/ZnSe/ZnS core-shell structure.

[Comparative Synthesis Example 2: Synthesis of Quantum Dots with Unsubstituted Ligands (A22)]

0.4 mmol (0.058 g) of indium acetate, 0.6 mmol (0.15 g) of palmitic acid, and 20 mL of 1-octadecene were added to the reactor and heated to 120°C under vacuum. After 1 hour, the atmosphere in the reactor was converted to nitrogen.

After the mixture was heated to 280°C, a mixed solution of 0.2 mmol (58 μl ) of tris(trimethylsilyl)phosphine (TMS3P) and 1.0 mL of trioctylphosphine was quickly injected into it and reacted for 0.5 minutes.

Subsequently, 2.4 mmol (0.448 g) of zinc acetate, 4.8 mmol of oleic acid, and 20 mL of trioctylamine were added to the reactor and heated to 120°C under vacuum. After 1 hour, the atmosphere in the reactor was converted to nitrogen, and the reactor temperature was increased to 280°C. 2ml of the previously synthesized InP core solution was added, then 4.8mmol of selenium in trioctylphosphine solution (Se/TOP) was added thereto, and the final mixture was allowed to react for 2 hours. Ethanol was added to the reaction solution that was rapidly cooled to room temperature, and centrifuged. The obtained precipitate was filtered under reduced pressure, and then dried under reduced pressure to obtain a core-shell of InP/ZnSe.

Subsequently, 2.4 mmol (0.448 g) of zinc acetate, 4.8 mmol of oleic acid and 20 mL of trioctylamine were added to the reactor and heated to 120°C under vacuum. After 1 hour, the atmosphere in the reactor was converted to nitrogen, and the reactor temperature was increased to 280°C. 2ml of the previously synthesized InP/ZnSe core-shell solution was added, then 4.8mmol of sulfur trioctylphosphine solution (S/TOP) was added thereto, and the final mixture was allowed to react for 2 hours. Ethanol was added to the reaction solution that was rapidly cooled to room temperature, and centrifuged. The obtained precipitate was filtered under reduced pressure, and then dried under reduced pressure to obtain quantum dots having an InP/ZnSe/ZnS core-shell structure.

[Comparative Synthesis Example 3: Synthesis of Ligand Substituted Quantum Dots (A23)]

The quantum dots were synthesized in the same manner as in Synthesis Example 3 except that the compound (1-dodecyl mercaptan) represented by the following chemical formula a was used instead of the ligand used in Synthesis Example 3.

〔Chemical formula a〕CH ₃ (CH ₂ ) ₁₀ CH ₂ SH

[Comparative Synthesis Example 4: Synthesis of Ligand Substituted Quantum Dots (A24)]

The quantum dots were synthesized in the same manner as in Synthesis Example 3 except that the compound represented by the following Chemical Formula b was used instead of the ligand used in Synthesis Example 3.

[Chemical formula b] H ₂ NCH ₂ (CH ₂ ) ₉ CH ₂ NH ₂

[Preparation Example 1: Preparation of Scattering Particle Dispersion Liquid (C1)]

_{70.0 parts by weight of TiO 2} with a particle size of 210nm (Ishihara Corporation CR-63) as scattering particles, 4.0 parts by weight of DISPERBYK-2001 (BYK Corporation) as a dispersant, and 26 parts by weight of 1,6-hexanediol diacrylic acid The ester was used as a solvent, and the above-mentioned materials were mixed and dispersed using a bead mill for 12 hours to prepare a scattering particle dispersion (C1).

[Examples and Comparative Examples: Preparation of Light Conversion Ink Composition]

The light conversion ink composition was prepared by mixing the components shown in Table 1 to Table 4 below (unit: wt%).

A1 to A24: Quantum dots prepared in Synthesis Examples 1 to 24.

B1: 1,6-hexanediol diacrylate (Sigma-Aldrich Corporation)

B2: 1,9-bispropenyloxynonane (TCI Co.,Ltd.)

B3: Tripropylene glycol diacrylate (Sigma-Aldrich Corporation)

B4: Trimethylolpropane triacrylate (A-TMPT, Shin Nakamura Chemical Co., Ltd.)

B5: Ethoxylated pentaerythritol tetraacrylate (ATM-4E, Shin Nakamura Chemical Co., Ltd.)

B6: Dipentaerythritol hexaacrylate (A-9550, Shin Nakamura Chemical Co., Ltd.)

C1: Scattering particle dispersion prepared in Preparation Example 1

D1: Irgacure OXE-01 (BASF Corporation)

E1: SH8400 (Dow Corning Toray Silicone Co., Ltd.)

〔Experimental example〕

By using the light conversion ink compositions prepared in the Examples and Comparative Examples, a light conversion coating was prepared as described below. The film thickness, brightness, dispersion, and viscosity were measured by the following methods, and the results are shown in Table 5-6 below.

<Preparation of Light Conversion Coating>

The various light conversion ink compositions prepared in the examples and comparative examples were coated on a 5cm x 5cm glass substrate by an inkjet method, and a 1KW high pressure mercury vapor lamp containing all g, h and i lights was used as the ultraviolet light source to radiation intensity 1,000mJ / cm ² of radiation, and then heated at 180 [deg.] C oven for 30 minutes to prepare light conversion coating.

(1) Film thickness

The film thickness of the light conversion coating prepared above was measured with a film thickness measuring device (Dektak 6M, Veeco Instruments, Inc.).

(2) Brightness

The light conversion coating prepared above was placed on a blue light source (XLamp XR-E LED, Royal blue 450, Cree, Inc.), and a brightness measuring device (CAS140CT Spectrometer, Instrument systems) was used to measure the brightness during blue light irradiation.

(3) Dispersibility

In the process of preparing the light conversion ink composition, the liquid sample before adding the scattering particles was confirmed with the naked eye, and evaluated according to the following evaluation criteria.

<Evaluation Criteria>

○: Transparent state

×: Turbid state

(4) Viscosity

The viscosity of the light conversion ink composition was measured using an R-type viscometer (VISCOMETER MODEL RE120L SYSTEM, Toki Sangyo Co., Ltd.) at a rotation speed of 20 rpm and a condition of 30°C.

As shown in Table 5 to Table 6 above, it is confirmed that the light conversion ink composition of Examples 1 to 30 includes a polyethylene glycol-based ligand according to the present invention. Quantum dots with specific bifunctional (meth)acrylates as curable monomers exhibit excellent quantum dot optical properties and dispersibility, and achieve low viscosity. On the other hand, in the case of the light conversion ink composition of Comparative Examples 1 to 12, it does not include a specific bifunctional (meth)acrylate as a curable monomer, and the light conversion ink composition of Comparative Examples 12 to 24 In the case of a substance, which contains quantum dots that do not have a polyethylene glycol ligand based on the present invention, the brightness is reduced and the dispersibility is deteriorated, making the liquid sample turbid and too high to be measured with the device.

Although specific parts of the present invention have been described in detail, it is obvious to those with ordinary knowledge in the technical field of the present invention that these specific disclosures are merely preferred embodiments, and the scope of the present invention is not limited thereto. In addition, those with ordinary knowledge in the technical field of the present invention will understand that various applications and modifications can be made without departing from the scope and spirit of the present invention based on the above description.

Therefore, the essential scope of the present invention will be defined by the appended claims and their equivalents.

Claims (11)

A light conversion ink composition comprising a quantum dot and a curable monomer, wherein the quantum dot has a coordination base layer, and at least one compound represented by the following chemical formulas 1a to 1e is included on the surface of the coordination base layer , And the curable monomer includes a compound represented by the following chemical formula 2, wherein based on 100% by weight of the light conversion ink composition, the light conversion ink composition includes a solvent with a content of 2% by weight or less:

〔Chemical formula 2〕

Wherein, R'and R" are each independently a hydrogen atom; a carboxyl group; a phenyl group; or an unsubstituted or substituted C ₁ -C ₂₀ alkyl group with a thiol group, and R'and R" are not hydrogen atoms at the same time; a phenyl group; Or an unsubstituted C ₁ -C ₂₀ alkyl group, R ^a , R ^b and R ^c are each independently a C ₁ -C ₂₂ alkyl group or a C ₄ -C ₂₂ alkenyl group, and R ^d is a C ₁ -C ₂₂ alkylene group , C ₃ -C ₈ cycloalkylene or C ₆ -C ₁₄ arylene, A and B each independently does not exist, or C ₁ -C ₂₂ alkylene, O, NR or S, R is hydrogen or C ₁ -C ₂₂ alkyl group, X is carboxyl group, phosphoric acid group, thiol group, amino group, tetrazolyl, imidazolyl, pyridyl or lipoic amide group, n is an integer from 1 to 20, p, q, t And u are each independently an integer from 1 to 100, r is an integer from 1 to 10, R ¹ is C ₁ -C ₂₀ alkylene, phenylene or C ₃ -C ₁₀ cycloalkylene, R ² is Hydrogen or methyl, and m is an integer from 1 to 15. The light conversion ink composition according to claim 1, wherein the quantum dot is a non-cadmium type quantum dot. The light conversion ink composition according to claim 2, wherein the quantum dot has a core-shell structure, the core-shell structure has a core and a shell covering the core, wherein the core includes selected from GaN, GaP, GaAs, GaSb, AlN, AlP, AlAs, AlSb, InN, InP, InAs, InSb, GaNP, GaNAS, GaNSb, GaPAs, GaPSb, AlNP, AlNAs, AlNSb, AlPAs, AlPSb, InNP, InNAs, InNSb, InPAs, InPSb, GaAlNP, At least one of the group consisting of GaAlNAs, GaAlNSb, GaAlPAs, GaAlPSb, GaInNP, GaInNAs, GaInNSb, GaInPAs, GaInPSb, InAlNP, InAlNAs, InAlNSb, InAlPAs, and InAlPSb, and the shell includes selected from ZnSe, ZnS and ZnTe At least one of the formed groups. The light conversion ink composition according to claim 1, further comprising a scattering particle. The light conversion ink composition according to claim 4, wherein the scattering particles include selected from Al ₂ O ₃ , SiO ₂ , ZnO, ZrO ₂ , BaTiO ₃ , TiO ₂ , Ta ₂ O ₅ , Ti ₃ O ₅ , ITO , IZO, ATO, ZnO-Al, Nb ₂ O ₃ , at least one of the group consisting of SnO and MgO. The light conversion ink composition according to claim 5, wherein the scattering particles are TiO ₂ . The light conversion ink composition according to claim 1, further comprising a photopolymerization initiator. The light conversion ink composition according to claim 1, including solvent-free. A light conversion pixel includes a cured product of the light conversion ink composition according to any one of claim 1 to claim 8. A color filter comprising the light conversion pixel as described in claim 9. An image display device having the color filter according to claim 10.